JP4046412B2 - Engine fuel injector - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an engine fuel injection apparatus in which fuel is directly supplied to a cylinder bore.
[0002]
[Prior art]
An engine fuel injection device in which fuel is directly injected into a cylinder bore is pressurized to a required injection pressure by a high-pressure fuel pump, and the high-pressure fuel is supplied to a fuel injection valve via a high-pressure fuel passage. It is configured.
[0003]
Therefore, in this type of fuel injection device, it is necessary to further improve the sealing performance of each part of the high-pressure fuel system as compared with the carburetor type and the EFI type that injects fuel into the intake system.
[0004]
[Problems to be solved by the invention]
However, the conventional fuel injection device employs a structure in which the high pressure fuel pump, which is a high pressure fuel system component, a fuel supply rail, a fuel injection valve, and the like are individually attached to the engine. The seal inspection must be performed after the parts are mounted on the engine and the engine is running. Therefore, the seal part of each part is hidden by the shadow of other parts and is difficult to see, making it difficult to reliably check the seal performance. There is a problem that.
[0005]
In addition, since the high pressure fuel system parts are individually attached to the engine, there is a problem that the number of assembly steps of the high pressure fuel system is large.
[0006]
The present invention has been made in view of the above-described conventional problems, and can easily and reliably inspect the sealing performance of the entire high-pressure fuel system before engine operation, and can reduce the number of assembly steps for the engine of the high-pressure fuel system. It aims at providing the fuel-injection apparatus of the engine which can be reduced.
[0007]
[Means for Solving the Problems]
  According to the first aspect of the present invention, a fuel injection valve that injects fuel into a cylinder bore, a high-pressure fuel pump that is driven by an engine and boosts the fuel to a required injection pressure, and fuel from the high-pressure fuel pump is injected into the fuel. A high-pressure fuel passage to be supplied to the valve, and a fuel pressure adjustment valve for adjusting the fuel pressure in the high-pressure fuel passage to the injection pressure.A high-pressure fuel assembly that is unitizedIn the fuel injection device for a V-type vertical engine for an outboard motor, the high-pressure fuel passage is made of an aluminum alloy and arranged in a horizontal direction, and is made of an aluminum alloy and is placed vertically in parallel with the crankshaft. The left and right fuel supply rails, which are arranged and connected to the fuel injection valves, are composed of three parts. The delivery of the left and right fuel supply rails above the uppermost fuel injection valve A pipe is connected, the delivery pipe and the high-pressure fuel pump are integrated through a unitization bracket, and the bracket is fixed to the engine.
[0008]
In the present invention, the unitization of the high-pressure fuel system parts into the high-pressure fuel system assembly corresponding to the state assembled to the engine means that the same pressure as in the operating state is applied to the assembly to This means that the sealability of each seal part is unitized to such an extent that it can be inspected at the same time.
[0009]
The invention of claim 2 is characterized in that, in claim 1, the high-pressure fuel control valve is built in a high-pressure fuel pump.
[0010]
According to a third aspect of the present invention, in the first or second aspect, the high-pressure fuel passage includes a fuel supply rail and a delivery pipe, and the high-pressure fuel pump, the fuel pressure adjustment valve, and the delivery pipe are included in the first assembly. The fuel supply rail and the fuel injection valve are unitized into a second assembly, and the first and second assemblies are separately mounted on the engine.
[0011]
  The invention of claim 43. The high pressure fuel pump assembly according to claim 1, wherein both the high pressure fuel pump side portion and the fuel injection valve side portion of the high pressure fuel system assembly are fixed to the engine.It is characterized by.
[0012]
  The invention of claim 55. The fuel injection valve according to claim 1, wherein the fuel injection valve is fixed to the fuel supply rail by detachably fixing the adapter locked to the fuel injection valve to the fuel supply rail.It is characterized by.
[0013]
  The invention of claim 66. The fuel injection valve according to claim 5, wherein when the fuel supply rail is pressed and fixed to the cylinder head, the adapter presses the fuel injection valve with a sealing member made of an elastic member on a seal surface on the cylinder head side. Be fixed to the cylinder headIt is characterized by.
[0014]
  The invention of claim 77. The method according to claim 1, wherein at least a part of the high-pressure fuel system assembly is located in the V bank and fixed to the bottom of the V bank when viewed in the bisector direction of the V bank. WhatIt is characterized by.
[0015]
  The invention of claim 88. The bank fuel supply rails according to claim 7, wherein the fuel supply rails for each bank are arranged in parallel to the crankshaft and closer to the inner side of the V bank than the cylinder shaft, and the fuel injection valves connected to both the fuel supply rails are divided into two equal parts of the V bank. Arranged almost parallel to the lineIt is characterized by.
[0016]
  The invention of claim 99. The vapor separator for storing fuel from a fuel tank and containing return oil from the high-pressure fuel system as a unit in the high-pressure fuel assembly according to claim 7, wherein the vapor separator is the V bank. Installed in the engine so that it is located insideIt is characterized by.
[0017]
  The invention of claim 10A ship equipped with a high-pressure fuel pump that boosts fuel to a required injection pressure and a high-pressure fuel pipe that supplies fuel from the high-pressure fuel pump to a fuel injection valve, and injects fuel into an intake system or a cylinder bore. In the fuel injection device for a V-type vertical engine for an external unit, the high-pressure fuel pipe is made of an aluminum alloy, and two fuel supply rails arranged vertically in the cylinder head portion of each bank in parallel with the crankshaft. A delivery pipe which is made of an aluminum alloy and is arranged in the horizontal direction and connects the upper ends of the fuel supply rails, and the delivery pipe and the high-pressure fuel pump are integrated via a unitization bracket. The bracket is fixed to the engine,A joint pipe is inserted into a rail side connection hole formed in the fuel supply rail and a delivery pipe side connection hole formed in the delivery pipe so as to be coaxial with the rail side connection hole, and the joint pipe and the rail Between the side connection hole and the delivery pipe side connection hole, there must be a heat-insulating elastic seal ring.It is characterized by.
[0018]
  The invention of claim 11In Claim 10, the backup ring which prevents that the said seal ring deform | transforms abnormally by pressure is interposed between the said joint pipe, the said rail side connection hole, and the delivery pipe side connection hole.It is characterized by that.
[0023]
[Effects of the invention]
According to the first aspect of the invention, it corresponds to a state in which at least two parts of the high-pressure fuel system parts including the fuel injection valve, the high-pressure fuel pump, the high-pressure fuel passage, and the fuel pressure regulating valve are assembled to the engine. Since it is unitized into a high-pressure fuel system assembly, it is possible to apply the same pressure to the high-pressure fuel system parts in the state of the high-pressure fuel assembly in the state of the high-pressure fuel assembly before the engine is operated. Since the seal part can be easily visually checked, the sealability can be easily and reliably inspected.
[0024]
  In addition, since the high-pressure fuel system parts are unitized into a high-pressure fuel system assembly corresponding to the state assembled to the engine, this assembly can be attached to the engine almost as it is, and the assembly of the high-pressure fuel system parts into the engine is as much as it is. Man-hours can be reduced.
  Further, since the bracket for unitizing the fuel supply rail portion and the high-pressure fuel pump is fixed to the engine, only one unitization bracket and one engine fixing bracket are required, and the number of parts can be reduced.
[0025]
According to the second aspect of the present invention, the fuel pressure adjustment valve for adjusting the fuel pressure in the high-pressure fuel passage to the injection pressure is built in the high-pressure fuel pump. The possible range can be further expanded, and the number of assembling steps for the engine of the high-pressure fuel system parts can be further reduced.
[0026]
According to the invention of claim 3, since the first assembly of the high-pressure fuel pump and the delivery pipe and the second assembly of the fuel injection valve and the fuel supply rail are unitized, the first and second assemblies are separated. In addition, the sealability can be inspected, and the first and second assemblies can be mounted on the engine as they are, so that the number of assembling steps can be reduced accordingly.
[0028]
  Claim4According to the invention, both the high-pressure fuel pump side portion and the fuel injection valve-side portion of the high-pressure fuel system assembly are fixed to the engine. Since the portion is fixed to the engine, the strength of attaching the assembly to the engine can be increased.
[0029]
  Claim5According to the invention, the fuel injection valve is fixed to the fuel supply rail by removably fixing the adapter locked to the fuel injection valve to the fuel supply rail. With a simple structure, the fuel injection valve can be assembled to the fuel supply rail, and the above-described sealability inspection before engine mounting can be realized.
[0030]
  Claim6According to the invention, when the fuel supply rail is pressed and fixed to the cylinder head, the adapter is configured to press the fuel injection valve with the sealing member made of an elastic member on the seal surface on the cylinder head side. The fuel injection valve fixing member itself can be used as well, and the bracket for attaching the fuel injection valve, which has been conventionally required, can be eliminated, and the number of assembly steps can be reduced.
[0031]
  Claim7According to the invention, in the V-type engine, the high-pressure fuel system assembly is positioned in the V bank when viewed in the bisector direction of the V bank and is fixed to the bottom of the V bank. The high-pressure fuel system can be arranged using the V bank space, and the entire engine can be made compact.
[0032]
  Claim8According to this invention, the fuel supply rails for each bank are arranged in parallel to the crankshaft and closer to the inside of the V bank than the cylinder shaft, and the fuel injection valves connected to both the fuel supply rails are divided into two equal parts of the V bank. Since it is arranged substantially parallel to the line, the high-pressure fuel system assembly can be attached to the engine in the V-type engine. That is, in the case of a V-type engine, the high pressure fuel system assembly cannot be assembled to the engine as it is depending on the direction in which the fuel injection valve is inserted into the cylinder head. However, in the present invention, the direction in which the fuel injection valve is inserted into the cylinder head. Is made substantially parallel to the bisector of the V bank, so this problem can be avoided.
[0033]
  Claim9According to the invention, the vapor separator is unitized into the high-pressure fuel assembly, and the assembly is attached to the engine so that the vapor separator is located in the V-bench, so that the high-pressure fuel pipe length is minimized. In addition, the unit including the preload fuel system parts can be unitized, and the entire engine can be further downsized.
[0034]
  Claim10According to the invention, since the high-pressure fuel pipe is made of an aluminum alloy, the weight can be reduced as compared with a conventional iron high-pressure fuel pipe, and the seawater resistance is higher than that of an iron-made one.sexIt can be used for outboard motors used at sea.
[0035]
The high-pressure fuel pipe is divided into at least two parts, the passage holes of the divided high-pressure fuel pipes are connected by a joint pipe, and a seal ring made of an elastic member having heat insulation between the joint pipe and the passage hole Therefore, vibration and heat transfer from one part to the other part can be suppressed.
[0036]
  That is, two fuel supply rails arranged vertically in a V-type vertical engine and the upper ends of both fuel supply rails are connected to each other.Since a seal ring made of an elastic member with heat insulation is interposed in the connection part with the delivery pipe,From the fuel supply rail sideDelivery pipeThe heat transfer to the side can be cut off, the fuel temperature in the fuel supply rail can be raised, the atomization of the fuel is promoted, and the combustion state of the engine is improved.
[0037]
  According to the invention of claim 11,Since the backup ring is interposed between the joint pipe, the rail side connection hole, and the delivery pipe side connection hole, the seal ring can be prevented from being deformed abnormally by pressure, and sealing performance can be secured.
[0040]
Embodiment
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
1 to 23 are views for explaining an engine fuel injection device according to an embodiment of the present invention. FIG. 1 is a block diagram showing the overall configuration, FIG. 2 is a plan view, and FIG. 3 is a sectional plan view. 4 is a side view, FIG. 5 is a rear view, FIGS. 6 and 7 are cross-sectional side views of the cylinder bore portion, cross-sectional plan views, FIGS. 8 and 9 are plan views, side views, and FIGS. FIG. 11 is a plan view and a side view of the pump unit of the high-pressure pump unit, FIGS. 12, 13 and 14 are a plan view, a cross-sectional front view and a cross-sectional side view of the delivery pipe, and FIGS. Rail top view, cross-sectional front view, cross-sectional side view, FIG. 18 is an enlarged cross-sectional view of the connecting portion between the delivery pipe and the fuel supply rail, and FIGS. 19, 20, and 21 are a plan view, rear view, and side view of the unit bracket. Figures 22 and 23 are plan views of the cylinder head, It is a surface view.
[0041]
In the figure, reference numeral 1 denotes an outboard motor that is mounted on the tail of the hull so that it can swing up and down and turn left and right. The outboard motor 1 has an upper case 1b coupled to an upper portion of a lower case 1a provided with a propulsion device, The engine 2 is mounted on the upper case 1b and has a schematic structure in which the periphery is surrounded by a top cowl 1c.
[0042]
The engine 2 is a water-cooled two-cycle V-type six-cylinder crankshaft vertical type, and a crankcase 4 is coupled to a front mating surface of a cylinder block 3 formed so as to form a V bank, The cylinder head 5 and the head cover 6 are laminated and connected to the surface, and the piston 7 is slidably inserted into each cylinder bore 3a formed in each bank cylinder portion of the cylinder block 3. It has a schematic structure connected to a crankshaft 9 by a connecting rod 8. The crankshaft 9 is disposed in a crank chamber 9a composed of the crankcase 4 and the cylinder block 3, and is substantially vertical when the outboard motor 1 is in a normal running state. Eggplant.
[0043]
A throttle body 45 containing a throttle valve 45b is connected to each crank chamber 9a through a backflow prevention reed valve 45a, and an intake silencer 46 is connected to the upstream side of the throttle body 45. The intake port 46a of the intake silencer 46 is located on the left side as viewed in FIG. 2, and opens toward the V bank side.
[0044]
Three sets of combustion recesses 5a that form combustion chambers with the cylinder bores 3a and the top surfaces of the pistons 7 are formed on the cylinder block side mating surface portion of the cylinder head 5, and the outer side of each combustion recess 5a ( The rear side is surrounded by a water cooling jacket 5b. The water cooling jacket 5b is formed by combining a recess formed on the cylinder head 5 side and a recess formed on the head cover 6 side. A spark plug 11 is screwed into the cylinder head 5 so as to be coaxial with the cylinder axis A, which is the axis of the cylinder bore 3a, and the electrode 11a of the spark plug 11 is located at the center of the inner surface of the combustion recess 5a. It is located in the electrode boss 5h formed so as to protrude slightly.
[0045]
As shown in FIG. 3, a cooling jacket 3 g having a triangular cross section and extending in parallel with the crankshaft 9 is integrally formed at the bottom of the V bank of the cylinder block 3. A throttle hole (not shown) for restricting the discharge of the cooling water is formed at the bottom of the cooling jacket 3g, so that the cooling jacket 3g is always filled with the cooling water.
[0046]
Exhaust merging grooves 3c and 3c are formed in a groove shape outside the cooling jacket 3g at the bottom of the V bank of the cylinder block 3 so that the exhaust ports 3b that open to the cylinder bores 3a merge at the left and right banks. The exhaust junction grooves 3c, 3c and the inner cover 41 disposed so as to cover the exhaust junction grooves 3c, 3c form an exhaust junction passage. Exhaust gas from the cylinder bore 3a is discharged into the water at the lower portion of the outboard motor 1 through the exhaust pipes 10 and 10 from the exhaust merging passages.
[0047]
An outer cover 42 is disposed at the bottom of the V bank so as to cover the outer side of the inner cover 41, and a space between the water cover 42 and the inner cover 41 serves as a cooling jacket 43. The cooling water is supplied to the bottom of the cooling jacket 43, from which a part thereof is introduced into the cooling jacket 5b of each cylinder, and the rest is introduced into the cooling jacket 3g at the upper end of the cooling jacket 43. It is discharged below the engine. Therefore, the exhaust merging passage of this embodiment is sandwiched between the cooling jackets 3g and 43, and thus sufficient cooling performance is ensured.
[0048]
A flat ECU bracket 47 is bolted and fixed to the outer side surface (rear side surface) of the outer cover 42 via a number of rubber mounts 48, and the control device 32 is attached to the back side of the bracket 47. Yes. In addition, an injector driver 32 for driving and controlling a fuel injection valve 12, which will be described later, is mounted on the back surface of the control device 32, and ignition coils 58 are mounted on the left and right edges of the ECU bracket 47. Yes.
[0049]
The control device 32 includes an engine speed signal I1, a throttle opening signal I2, O₂Various signals such as an air-fuel ratio signal I3 from the sensor 57 and a tilt / trim angle signal I4 of the outboard motor 1 are input, and an optimal ignition timing signal O1 and a fuel injection control signal O2 corresponding to the signals are output. Further, the control device 32 notifies the pressure abnormality of the high pressure fuel system based on the fuel pressure signal I5 of the high pressure fuel system from the pressure sensor 30, and further controls the residual pressure to open the electromagnetic release valve 31 for a certain period after the engine is stopped. The signal O3 is output.
[0050]
Further, each cylinder bore 3a is opened so that one end side opening of the first and second scavenging ports (main scavenging ports) 3d and 3e is located on both sides of the exhaust port 3b, and the third scavenging port ( The opening on the one end side of the counter scavenging port 3f is opened so as to face the exhaust port 3b, and the openings on the other end of the first to third scavenging ports 3d to 3f open in the crank chamber 9a. . 57a is O₂This is an exhaust gas intake port of the sensor 57.
[0051]
Here, the first and second scavenging ports 3d and 3e are arranged so that the scavenging air flows in a direction substantially perpendicular to the cylinder axis A and away from the exhaust port 3b, that is, toward the third scavenging port 3f. An arrangement position and a shape are set. On the other hand, the arrangement position and shape of the third scavenging port 3f are set so that the scavenging air flows in the cylinder axis A direction.
[0052]
The scavenging air flow from the first to third scavenging ports 3d to 3f has the flow shown in FIGS. 6 and 7 show the scavenging airflow when the throttle valve is fully opened and the piston 7 is fixed at a position where the scavenging ports and exhaust ports are fully opened (substantially bottom dead center) as indicated by a two-dot chain line. The flow of is schematically shown. In this case, most of the scavenging air flow C3 from the third scavenging port 3f rises in the direction of the cylinder axis A along the inner surface of the cylinder bore 3a on the side opposite to the exhaust port 3b from the third scavenging port 3f, and enters the combustion recess 5a. Is reversed downward, descends the exhaust port 3b side portion of the cylinder bore 3a, and flows out into the exhaust port 3b.
[0053]
On the other hand, most of the scavenging air flows C1 and C2 from the first and second scavenging ports 3d and 3e flow from the first and second scavenging ports 3d and 3e toward the third scavenging port 3f in the cylinder bore 3a. Thereafter, it merges with the scavenging air flow C3 from the third scavenging port 3f, rises in the direction of the cylinder axis A together with the scavenging air flow C3, reverses downward in the combustion recess 5a, and lowers the exhaust port 3b side portion of the cylinder bore 3a And flows out into the exhaust port 3b.
[0054]
As a result of each of the scavenging air flows C1 to C3 as described above, the residual gas B3 is present in the upper part of the cylinder bore 3a and the part extending over the combustion recess 5a and closer to the exhaust port 3b, and the first and first gas in the cylinder bore 3a. Residual gases B1 and B2 are likely to remain near the upper openings of the second scavenging ports 3d and 3e. When these residual gases B1 to B3 are viewed in the direction of the cylinder axis A (see FIG. 7), the residual gases B1 to B3 are along the inner surface of the cylinder bore 3a and in the portions closer to the first and second scavenging ports 3d and 3e and the exhaust port 3b. positioned.
[0055]
The cylinder head 5 is provided with a fuel injection valve 12 that constitutes a part of the fuel injection device 13 and supplies fuel directly into the cylinder bore 3a for each cylinder. Each fuel injection valve 12 is inserted obliquely into a mounting hole 5e of a boss portion 5d formed on the cylinder head 5 near the residual gas B3, and the injection nozzle 12a opens into the combustion recess 5a. Is inserted into the injection hole 5c.
[0056]
The axis D of the fuel injection valve 12 intersects the cylinder axis A and intersects the top surface of the piston 7 at the position where the scavenging ports and exhaust ports are fully opened (substantially bottom dead center) at the intersection D1. It extends.
[0057]
The nozzle shape of the injection nozzle 12a of the fuel injection valve 12 is set so as to inject the fuel G into a shape along a conical outer surface (so-called hollow cone shape) as shown in FIGS. Yes. Thereby, the injected fuel G from the fuel injection valve 12 easily collides with the residual gases B1 to B3. Further, the injected fuel G faces the portions of the scavenging airflows C3 and C1, C2 that flow in the vicinity of the combustion recess 5a and easily collides.
[0058]
Here, the fuel injection timing and period from the fuel injection valve 12 are controlled as follows. That is, in the idling operation region in the throttle fully closed state, the scavenging ports 3d to 3f are injected in the range of 3 to 10 degrees in crank angle from the time when the scavenging ports 3d to 3f are fully closed. In order to prevent blow-through, it is desirable to inject after the exhaust port 3b is fully closed. In this embodiment, the timing at which the injected fuel reaches the exhaust port 3b when the exhaust port 3b is fully closed is selected.
[0059]
In addition, in the high-speed rotation and high-load operation range where the throttle is fully opened, the fuel piston is injected in the range of 90 degrees from the bottom dead center of the fuel piston. In the middle opening of the throttle, the fuel is injected in the middle of the idling and high speed / high load operating range.
[0060]
In any of the above operating ranges, when the piston 7 rises from a position where the exhaust port 3b is fully closed, the injected fuel hits the substantially entire top surface of the piston 7. Note that the injected fuel G in FIG. 6 is shown by a two-dot chain line when the fuel is started to be injected when the piston 7 is at the bottom dead center, and a broken line when the piston fully closes the exhaust port 3b. Is shown.
[0061]
The fuel injector 13 includes a high-pressure fuel system 14 for supplying high-pressure fuel to the fuel injection valves 12, a pre-pressure fuel system 15 for supplying pre-pressure fuel to the high-pressure fuel system 14, and a low-pressure fuel for the pre-pressure fuel system 15. And a low-pressure fuel system 16 for supplying the fuel.
[0062]
The low-pressure fuel system 16 uses the fuel in the fuel tank 17 mounted on the hull side by two sets of low-pressure fuel pumps 18 through the low-pressure fuel pipes 19a to 19c and the drain filter 20, and the vapor separator 21 of the preload fuel system 15. It is comprised so that it may supply.
[0063]
Here, the drain filter 20, the low-pressure fuel pump 18, the low-pressure fuel pipes 19 a to 19 c, and the vapor separator 21 are arranged along the side wall surface of the engine 2. The two sets of low-pressure fuel pumps 18 and 18 are arranged so as to be positioned in the vertical direction and are connected in parallel, and a branching portion 19d from the drain filter 20 to the two pumps 18 and 18 has a lower-side low-pressure pump 18. Is disposed above the suction port 18a. As a result, bubbles generated in the piping are not sucked into the lower pump 18, and as a result, even when bubbles are generated due to temperature rise, flow path resistance of the suction path, etc., the fuel discharge amount is extremely reduced. The problem can be avoided.
[0064]
The preload fuel system 15 is boosted to a predetermined pressure by a preload pump 22 containing the fuel in the vapor separator 21 and supplied to the high pressure pump unit 24 of the high pressure fuel system 14 via a preload supply pipe 23a. The fuel returned from the high pressure regulator 25 for adjusting the fuel pressure supplied to the fuel injection valve 12 of the fuel system 14 is returned to the vapor separator 21 through the return pipe 23b. Reference numeral 26 denotes a preload regulator for adjusting the discharge side pressure of the preload pump 22, that is, the pressure in the preload supply pipe 23a, to a predetermined pressure, and 27 is a fuel cooler for cooling the return oil.
[0065]
The high-pressure fuel system 14 boosts the fuel supplied from the preload fuel system 15 to a predetermined pressure by the high-pressure pump unit 24, and injects the high-pressure fuel through the delivery pipe 28 and the fuel supply rails 29 and 29. The valve 12 is configured to be supplied.
[0066]
The high-pressure pump unit 24 has a structure in which the high-pressure pump main body 33 and the pump drive unit 34 are connected to each other by a bolt 39a so as to be disassembled. The high-pressure pump main body 33 is configured such that, when the high-pressure pump unit 24 is attached to the engine, the rotation axis E is directed in a direction (horizontal direction) perpendicular to the crankshaft 9. A preload fuel inlet 33a, a high pressure fuel outlet 33b, a high pressure fuel inlet 33c to the built-in high pressure regulator 25, and a return fuel outlet 33d from the high pressure regulator 25 are formed on the side surface of the high pressure pump main body 33. The preload fuel inlet 33a is connected to the preload supply pipe 23a, the high pressure fuel outlet 33b and the high pressure fuel inlet 33c are connected to the inlet 28a and outlet 28b of the delivery pipe 28, respectively, and the return fuel outlet 33d. Is connected to the return pipe 23b.
[0067]
When the high-pressure pump unit 24 is attached to the engine, the input shaft 35a of the pump drive unit 34 is parallel to the crankshaft 9, that is, in the vertical direction. An input pulley 36 fixed to the upper end of the input shaft 35 a of the pump drive unit 34 is connected to a drive pulley 38 fixed to the upper end of the crankshaft 9 by a transmission belt 37. The rotation of the input shaft 35a is transmitted to the output shaft 35c through a bevel gear 35b with the direction of the rotation axis changed by 90 degrees. The output shaft 35c is supported by a casing 34a via a ball bearing 35d and a flat bearing 35e, and the output shaft 35c is detachably coupled to the pump shaft 33e of the high-pressure pump main body 33. Thereby, the rotation of the crankshaft 9 arranged vertically can be transmitted to the pump shaft 33e of the high-pressure pump main body 33 arranged horizontally.
[0068]
A cooling jacket 34b for cooling the periphery of the bevel gear 35b, the ball bearing 35d and the like is formed in the casing 34a. The cooling jacket 34b is formed by combining a recess on the casing 34a side and a recess on the cover 34c side. The cooling jacket 34b is connected with a cooling hose 49 separated from the middle of the water supply pipe to the cooling jacket 43 formed at the bottom of the V bank, and the cooling water exiting the cooling jacket 34 is cooled. It is drained to the outside as pilot water to monitor that the water system is operating normally.
[0069]
The high-pressure pump body 33 includes a bypass passage 24b having a one-way valve 24a that allows only a flow from the upstream side (the preload fuel system 15 side) to the downstream side (the high-pressure fuel system 14 side), and the high-pressure regulator 25. Built-in. A pressure sensor 30 is connected to the delivery pipe 28.
[0070]
The pressure sensor 30 measures the fuel pressure by the low-pressure fuel system 15 before the engine is started and the high-pressure pump unit 24 is not operating, and measures the fuel pressure by the high-pressure fuel system 14 after the engine is started. Then, as described above, when the detected pressure is abnormal, the control device 32 generates a warning sound or turns on a warning lamp to detect an abnormality in the high-pressure fuel system. It functions as a warning means to notify.
[0071]
The delivery pipe 28 is disposed in a horizontal direction, and a fuel passage 28c is formed in a rod body having a rectangular cross section in the axial direction. Both left and right ends of the fuel passage 28c are closed with plugs 40, and Connection holes 28d are formed at the left and right ends of the fuel passage 28c.
[0072]
The left and right fuel supply rails 29 are arranged vertically in parallel with the crankshaft 9, and a fuel passage 29 a having a circular cross section is formed through a rod body having a rectangular cross section in the axial direction. In the middle of the fuel passage 29a, three sets of fuel supply ports 29c into which the fuel inlet portion 12b of the fuel injection valve 12 is inserted are branched in the direction perpendicular to the axis. A connection hole 29b is formed at the upper end of the fuel passage 29a so as to have a larger diameter than the fuel passage 29a, and the lower end is closed by a plug 40. Furthermore, an adapter mounting hole 29e is formed through the fuel supply rail 29 on the back side of each fuel supply port 29c, and rail fixing holes 29d are formed between the fuel supply ports 29c and 29c and at both ends.
[0073]
The left and right connection holes 28d of the delivery pipe 28 are connected to the upper side by a connection hole 29b at the upper end of the fuel passage 29a of the fuel supply rail 29, that is, the fuel injection valve 12 positioned at the uppermost position. In the present embodiment, the connection hole 29b is a fuel supply port to the fuel supply rail 29, and is also a fuel return port from the rail. The high-pressure fuel pipe for supplying high-pressure fuel from the high-pressure pump unit 24 to the fuel injection valve 12 is an aluminum alloy delivery pipe (communication pipe) 28 and aluminum alloy left and right fuel supply rails 29, 29. It is divided into three parts. The delivery pipe 28 and the fuel supply rail 29 are coupled by a bracket 53 and a bolt 53a. A cylindrical joint pipe 52 is inserted into the joint pipe 52 and the connection holes 28 d and 29 b of the fuel supply rail 29. Further, an O-ring 59 made of an elastic member having heat insulation properties such as rubber is attached to the seal groove 52a formed in the joint pipe 52, and the O-ring 59 is oil-tight on the inner surfaces of the connection holes 28d and 29b. Is in contact with Reference numeral 54 denotes a ring-shaped backup ring made of Teflon, which has a function of preventing the O-ring 59 from being deformed abnormally by pressure and ensuring a sealing property.
[0074]
The high-pressure fuel system 14 has a bypass passage 25a that bypasses the high-pressure regulator 25, and an electromagnetic release valve 31 is interposed in the bypass passage 25a. The opening / closing timing of the electromagnetic release valve 31 is controlled by the control unit (ECU) 32. That is, the electromagnetic release valve 31 opens when a predetermined time elapses after the engine is stopped, thereby functioning also as a residual pressure control means for setting the fuel pressure in the high pressure fuel system 14 and the preload fuel system 15 to substantially atmospheric pressure.
[0075]
Here, since the release valve 31 is opened, the amount of decompression fuel necessary to bring the fuel pressure in the high-pressure fuel system 14 and the preload fuel system 15 to substantially atmospheric pressure returns to the vapor separator 21. The vapor separator 21 is provided with a surplus space sufficient to accommodate the fuel for decompression.
[0076]
The high-pressure fuel system 14 in this embodiment is unitized as described in detail below. The delivery pipe 28 is fixed with bolts 39b on three pipe bosses 50a of the unit bracket 50, and the high pressure pump unit 24 is fixed with bolts 39c on one pump boss 50b. The high pressure fuel outlet 33b and the high pressure fuel inlet 33c are connected to the inlet 28a and outlet 28b of the delivery pipe 28. Thus, the first assembly of the high pressure fuel system is configured. Here, the fuel inlet 33 a of the high-pressure pump unit 24 is located above the fuel outlet of the vapor separator 21.
[0077]
The fuel inlet 12b of the fuel injection valve 12 is inserted into the three fuel supply ports 29c of the fuel supply rail 29, and the fuel injection valve 12 is fixed to the fuel supply rail 29 by an adapter 51 having a substantially C-shaped cross section. In detail, the latching step portion 51 a of the adapter 51 is locked between the latching flanges 12 c and 12 d of the fuel injection valve 12, and the bolt 39 d is inserted into the adapter mounting hole 29 e of the fuel supply rail 29 to insert the adapter 51. Each fuel injection valve 12 is fixed to the fuel supply rail 29 by screwing into the fuel supply rail 29. As a result, a second assembly (supply rail / injection valve assembly) of the high-pressure fuel system is formed, and the gap between the fuel supply port 29c and the fuel inlet portion 12b is sealed by an O-ring R. As will be described later, it is sufficient to perform only the sealing function, and absorption functions such as manufacturing error and assembly error of each part are not required. The supply rail / injection valve assemblies for the bank cylinders are unitized via the first assembly.
[0078]
When the second assembly is attached to the engine, the fuel supply rail is inserted into the injection hole 5c of the cylinder head 5 while the injection nozzle 12a of each fuel injection valve 12 is fitted with an elastic seal member 55. 29 is brought into contact with a rail boss portion 5g formed integrally with the cylinder head 5 so as to protrude upward, and a bolt 39e is inserted into a rail fixing hole 29d of the fuel supply rail 29 and screwed into the rail boss portion 5g. As a result, the seal portion 12e of the fuel injection valve 12 presses the seal member 55 against the seal surface 5f of the cylinder head 5, and each of the fuel supply rails 29, the fuel injection valve is caused by elastic deformation or plastic deformation of the seal member 55. Manufacturing errors and assembly errors between the components 12 and the cylinder head 5 are absorbed, and the gap between the fuel injection valve 12 and the cylinder head 5 is sealed.
[0079]
The unit bracket 50 has a shape in which an engine side mounting portion 50e is formed to extend in front of the pump unit mounting surface 50d, and an engine mounting wall 50f is fixed to the lower surface. Therefore, when the first assembly is attached to the engine, the engine side attachment portion 50e and the engine attachment wall 50f of the unit bracket 50 are bolted and fixed to the engine using the bolt holes 50g and 50c.
[0080]
Here, it is possible to combine the first and second assemblies to make the entire high-pressure fuel system into one unit. For this purpose, the axis D of the fuel supply rails 29, 29 arranged symmetrically on the left and right with respect to the bisector F of the V bank and the fuel injection valve 12 mounted on the rails are divided into the bisectors. What is necessary is just to attach to the said cylinder head 5 so that it may become parallel to the line F. FIG. If the axis D is not slightly parallel to the bisector F, the mounting hole 5e and the injection hole 5c of the fuel injection valve 12 to the cylinder head 5 are replaced by the diameter of the fuel injection valve 12 and the injection nozzle 12a portion. It may be formed larger than the diameter. In this case, the unitized high-pressure fuel system assembly can be directly assembled to the engine in the bisector F direction.
[0081]
Next, the function and effect of the present embodiment device will be described.
A high-pressure pump bypass passage 24b for bypassing the high-pressure pump main body 33 is provided, and a one-way valve 24a that allows only the flow from the preload fuel system 15 to the high-pressure fuel system 14 is provided in the bypass passage 24b. Since the pressure of the preload fuel system 15 can be transmitted to the high pressure fuel system 14 when the main body 33 is not operated, and the pressure sensor 30 is provided in the delivery pipe 28 of the high pressure fuel system 14, the preload fuel system 15 is stopped when the engine is stopped. When the electromagnetic preload pump 22 is operated, the preload from the pump 22 is transmitted to the high pressure fuel system 15 via the one-way valve 24a, and the fuel pressure of the preload fuel system 15 can be checked by the pressure sensor 30. Become. That is, it is possible to check the pressures of both fuel systems 15 and 14 by one pressure sensor 30, and it is possible to prevent problems such as an increase in the number of parts, a complicated structure, and an increase in cost due to the provision of two fuel systems.
[0082]
Further, an electromagnetic pressure release valve 31 is provided in the bypass passage 25a of the pressure regulating valve 25 of the high pressure fuel system 14, and the discharge side of the pressure release valve 31 is connected to the return pipe 23b of the preload fuel system 15. During maintenance work of the system 14, the pressure of the high-pressure fuel system 14 can be released by opening the pressure release valve 31, and the maintenance workability of the high-pressure fuel system 14 can be improved.
[0083]
Further, since the fuel extracted at this time is collected by the vapor separator 21 through the return pipe 23b, the fuel does not leak to the outside. In this case, since the capacity of the vapor separator 21 is set to be larger than the amount of return oil necessary for releasing the pressure from the maximum storage amount, the fuel in the high pressure fuel system 14 is maintained during maintenance work of the high pressure fuel system 14 or the like. Can be reliably accommodated, and leakage to the outside can be prevented more reliably.
[0084]
Since the pressure release valve 31 is an electromagnetic valve and the pressure release valve 31 is opened for a predetermined time after the engine is stopped, the residual pressure of the high pressure fuel system 14 is automatically set to the preload fuel system 15 when the engine is stopped. The maintenance work is further facilitated.
[0085]
In this embodiment, the upper portions of both fuel supply rails 29 and 29 arranged vertically in each bank of the V-type engine are connected by a delivery pipe (communication pipe) 28, and the high-pressure fuel is connected to the delivery pipe 28. Since the pump body 33 and the high pressure regulator (pressure regulating valve) 25 are connected, when fuel is supplied to the fuel supply rail 29 when the engine is restarted, the air in the rail 29 naturally accumulates in the upper part by the supplied fuel. The air can be discharged to the outside through the air vent hole formed in the upper part or the high pressure fuel pump main body 33, the high pressure regulator 25, etc., and the air can be easily removed without remaining in the fuel supply rail 29. At the same time, the problem that air enters the fuel injection valve 29 and the fuel injection function is hindered can be avoided. When the high-pressure fuel pump main body 33 is operated, the air remaining in the upper part is pushed out to the fuel return pipe 23b side by the pump via the pressure regulating valve 25 and is discharged into the vapor separator 21. .
[0086]
Further, since the high-pressure fuel pump main body 33 and the high-pressure regulator 25 are directly connected to the delivery pipe 28, the length of the high-pressure fuel pipe can be shortened and the piping structure can be simplified.
[0087]
In this case, the high-pressure fuel pump main body 33 and the high-pressure regulator 25 are disposed in the delivery pipe 28 that connects the upper portions of the fuel supply rails 29 arranged vertically, that is, both the fuel supply port and the fuel return port are provided. Since they are installed together in the same upper part, both the high-pressure fuel supply pipe and the low-pressure fuel return pipe are collectively connected to the upper side of the fuel supply rail, and the lowest part of the conventional fuel supply rail Compared to the case where the fuel supply pipe and the fuel return pipe are formed on both the lower side and the upper side of the fuel supply rail, such as the case where the fuel is supplied to the fuel and the fuel is extracted from the uppermost portion, the total length of the pipe is shorter. As a result, the piping structure is simplified.
[0088]
Further, since the fuel supply rails 29, 29 of each bank are arranged symmetrically with a V bank bisector extending parallel to the crankshaft, the air in the fuel supply rails 29, 29 can be evenly drawn out. .
[0089]
When only the preload fuel system 15 is operated, the fuel from the preload fuel system bypasses the high-pressure fuel pump body 33 and can be supplied to the fuel supply rail 29. In this case, by operating the preload fuel system 15, fuel is supplied into the fuel supply rail 29, and the air in the fuel supply rail 29 accumulates in the upper part, so that the air bleeding operation can be performed more easily and reliably. It can be carried out.
[0090]
Furthermore, since the high-pressure fuel pump main body 33 and the high-pressure regulator 25 are arranged above the fuel outlet of the vapor separator 21, the air in the pipe is accumulated in the high-pressure fuel pump main body 33 and is pushed out from here to the return pipe 23b side. Therefore, air can be easily and reliably removed from this point.
[0091]
Further, since the water cooling jacket 34b is provided in the casing 34c of the pump drive unit 34 so as to surround the bevel gear mechanism (rotational force transmission mechanism) 35b, the bearing 35d, and the like, and the engine cooling water is supplied to the water cooling jacket 34b. It is possible to suppress the temperature increase of the bevel gear mechanism 35b portion that is easy to perform by absorbing heat of the cooling water, and it is possible to avoid performance degradation due to the temperature increase of the lubricating oil filled in the portion.
[0092]
Since the pump drive unit 34 has a structure in which the pulley 36 fixed to the input shaft 35a is rotationally driven by engine power, the pump drive unit 34 is cooled by the cooling air generated by the rotation of the pulley 36. Also from this point, it is possible to avoid a decrease in performance due to a rise in temperature of the pump drive unit 34 and, consequently, a rise in temperature of the lubricating oil filled in the pump drive unit 34.
[0093]
Here, if the blades for blowing are formed in the pulley 36, the cooling air can be supplied to the pump drive unit 34 more reliably, the temperature rise of the pump drive unit 34 can be prevented more reliably, and the temperature rise of the lubricating oil Performance degradation can be avoided. Further, if the heat dissipating fins are formed on the outer surface of the pump drive unit 34, the pump drive unit 34 can be more reliably cooled by the air flow or the like.
[0094]
Furthermore, in this embodiment, the high-pressure pump unit 24 includes at least the pump drive unit 34 in the vicinity of the outside air introduction opening 1d formed in the top cowl (cow ring) 1c surrounding the engine, and the intake air of the engine from the opening 1d. Since the air flow up to the intake port (suction port) 46a of the system is located in the middle of the air flow, the outside air sucked into the top cowl 1c from the top cowl 1c outside air introduction opening 1d by the rotation of the engine is The pump drive unit 34 is cooled as it flows toward the intake port 46a. This external airflow can also prevent the pump drive unit 34 from rising in temperature, and avoid performance degradation due to an increase in lubricating oil temperature.
[0095]
In addition, since the high pressure pump unit 24 incorporating the high pressure regulator 25 and the delivery pipe 28 are unitized in the first assembly, and the fuel injection valve 12 and the fuel supply rail 29 are unitized in the second assembly, before attaching to the engine, In the state of the first and second assemblies, it is possible to apply the same pressure to the high-pressure fuel system parts as when the engine is operating, and in this pressurization state, the seal part of each part can be easily visually checked. Can be easily and reliably performed.
[0096]
In addition, since the high-pressure fuel system parts are unitized into the first and second assemblies so as to correspond to the state assembled to the engine, the first and second assemblies can be attached to the engine as they are. The number of assembly steps for fuel system parts to the engine can be reduced. After the first and second assemblies are attached to the engine, the delivery pipe 28 and the fuel supply rails 29 and 29 are connected by the bracket 53 and the bolt 53a.
[0097]
Since the unit bracket 50 for unitizing the delivery pipe 28 and the high-pressure pump unit 24 is fixed to the engine, only one unitizing bracket and engine fixing bracket are required, and the number of parts can be reduced.
[0098]
Further, the high pressure fuel system assembly formed by connecting the unitized first and second assemblies with the bracket 53 has both the high pressure pump unit 24 side portion and the fuel supply rail 29 side portion fixed to the engine. In other words, since the three portions of the high-pressure fuel system assembly that are spaced apart are fixed to the engine, the strength of mounting the assembly to the engine can be increased.
[0099]
When the fuel injection valve 12 is coupled to the fuel supply rail 29 via the adapter 51 to form a second assembly (supply rail / injection valve assembly), and the fuel supply rail 29 is pressed and fixed to the cylinder head 5, the fuel injection valve Since the 12 seal portions 12e are configured to press the seal member 55 against the seal surface 5f of the cylinder head 5, the fuel supply rail 29 itself can also be used as a fuel injection valve fixing member, which has been necessary in the past. A dedicated bracket for fuel injection valve installation can be eliminated and the number of assembly steps can be reduced. In addition, since manufacturing errors and assembly errors of each part can be absorbed by elastic deformation or plastic deformation of the seal member 55, the reliability of the sealing performance between the fuel supply rail 29 and each fuel injection valve 12 can be improved.
[0100]
That is, when it is necessary to secure the sealing performance that can withstand high-pressure fuel at the connecting portion between the fuel supply rail and the fuel injection valve and to absorb the error, there is a concern that the reliability of the sealing performance may eventually decrease. In the case of the present embodiment, it is not necessary to absorb the above error at the connection portion between the fuel supply rail and the fuel injection valve, and it is only necessary to ensure a sealing property that can withstand high-pressure fuel. Therefore, the reliability of this sealing property can be improved. .
[0101]
The high pressure fuel system assembly is positioned in the V bank when viewed in the bisector F direction of the V bank and is fixed to the bottom of the V bank, so that the high pressure fuel is utilized using the V bank space. The system can be arranged and the whole engine can be made compact.
[0102]
Here, each bank fuel supply rail 29 is arranged in parallel to the crankshaft 9 and closer to the inner side of the V bank than the cylinder axis A, and the axis D of the fuel injection valve 12 connected to both the fuel supply rails 29 is arranged. When arranged so as to be parallel to the bisector F of the V bank, the entire unitized high-pressure fuel system assembly can be attached to the engine as a unit. That is, in the case of a V-type engine, when the direction of insertion of the fuel injection valve 12 into the cylinder head is greatly deviated from the bisector F, for example, the fuel injection valve 12 and the mounting hole on the cylinder head side are The high pressure fuel system assembly cannot be assembled to the engine as it is because of interference, but this problem is caused when the insertion direction D of the fuel injection valve 12 into the cylinder head is parallel to the bisector F of the V bank. Can be avoided. As described above, even when the insertion direction D is slightly deviated from the bisector F, it is possible to attach the unit as a unit by giving the mounting hole a backlash.
[0103]
In this embodiment, since the high pressure fuel pipes such as the delivery pipe 28 and the fuel supply rail 29 are made of an aluminum alloy, the weight can be reduced as compared with the conventional high pressure fuel pipe made of iron, and the resistance is higher than that made of iron. It can improve seawater and can be used for outboard motors used at sea.
[0104]
In connecting the fuel supply rails 29 and 29 and the delivery pipe 28 that connects the upper ends of the fuel supply rails 29 and 29, the connection holes 28d and 29b are connected by a joint pipe 52, and the joint pipe is connected. Since the O-ring 59 made of an elastic member having heat insulation is interposed between the connection hole 28d and the connection holes 28d and 29b, the transfer of heat from the fuel supply rail 29 side to the delivery pipe 28 side can be cut off, and the fuel supply rail 29 The fuel temperature in the engine can be raised, which promotes fuel atomization and improves the combustion state of the engine.
[0105]
The arrangement direction of the fuel injection valve 12 and the shape of the injected fuel are set so that the fuel injected from the fuel injection valve 12 is directed to the residual gases B1 to B3 in the cylinder, and the fuel injection timing and period are set as described above. Since the predetermined conditions are set, it is possible to promote atomization and reduce blow-by. That is, the residual gases B1 to B3 in the cylinder are high in temperature, and the residual gas is generated at a portion where the flow velocity of the scavenging air flow is small. Therefore, by injecting fuel toward the remaining portion of the residual gas, the injection is performed. The fuel can be atomized with high-temperature gas in a short time, and the fuel injection target point is weak in the scavenging air, so that the injected fuel can be prevented from being blown through, and good combustion and improved exhaust gas properties can be achieved. Can do.
[0106]
Furthermore, since the fuel injected from the fuel injection valve is set to collide with the scavenging air flow C3 from the scavenging port through the combustion chamber 5a toward the exhaust port 3b, atomization is promoted by stirring with the scavenging air flow. Further, compared to the case where the injected fuel is injected in the same direction as the scavenging airflow, the injected fuel is less likely to be pushed away by the scavenging airflow, and as a result, the atomization of the fuel can be promoted and the blow-through can be suppressed.
[0107]
In this embodiment, the fuel injection valve 12 is disposed so as to inject fuel obliquely downward (in the direction D) from the position displaced from the cylinder axis A toward the exhaust port 3b toward the third scavenging port 3f. In addition, since the fuel is injected along the outer surface shape of the cone, the effect of promoting atomization and suppressing blow-through can be further obtained. That is, when the first and second scavenging ports 3d and 3e are provided on both sides of the exhaust port 3b, and the third scavenging port 3f is disposed so as to face the exhaust port 3b, the residual gases B1 to B3 are It is likely to occur along the inner surface of the cylinder bore 3a and at a portion between the exhaust port 3b and the fuel injection valve 12 and an upper portion of the first and second scavenging ports 3d and 3e. In this case, when fuel is injected from the fuel injection valve position along the outer surface shape of the cone, the injected fuel travels along the inner surface of the cylinder bore, and reliably collides with the residual gas. Opposing collision with the scavenging air.
[0108]
In the present embodiment, the injected fuel travels along the inner surface of the cylinder bore 3a and hardly adheres to the inner surface of the cylinder bore 3a. Therefore, the generation of HC is suppressed.
[0109]
Further, the injected fuel hits the exhaust port in the fully closed position or the entire top surface of the piston 7 closer to the combustion chamber, thereby preventing the piston 7 from overheating. If the fuel is directly injected into the cylinder bore as in the present embodiment, the lubricating oil supplied into the crank chamber becomes difficult to reach the piston pin boss portion from the back of the piston, and there is a problem that overheating is likely to occur. That is, in the two-cycle engine, the fuel supplied into the crankcase evaporates and cools the back surface of the piston, and this fuel carries the lubricating oil to the back surface of the piston. Is not supplied, so the above action cannot be obtained. On the other hand, as described above, the piston top surface is cooled with fuel to prevent overheating of the piston.
[0110]
FIG. 24 is a view for explaining a second embodiment of the high-pressure fuel pipe, in which the same reference numerals as those in FIG. 1 denote the same or corresponding parts. In the second embodiment, the delivery pipe 28 and the fuel supply rail 29 are provided from the delivery pipes 28 c and 29 a extending from the delivery pipe 28 to the lower ends of the fuel supply rails 29 and subsequently from the lower ends of the fuel supply rails 29. A reciprocating fuel passage comprising fuel return passages 29 a ′ and 28 c ′ returning to the pipe 28, the high-pressure fuel pump body 33 is connected to the fuel forward passage 28 c of the delivery pipe 28, and the high-pressure regulator 25 is connected to the delivery pipe 28. It is connected to the fuel return path 28c '.
[0111]
According to the second embodiment, in the delivery pipe 28 and the fuel supply rail 29, the reciprocating fuel passage comprising the fuel forward passages 28c and 29a and the fuel return passages 29a 'and 28c' extending subsequently thereto is provided, and the high-pressure fuel is provided. Since the pump main body 33 is connected to the fuel forward path 28c of the delivery pipe 28 and the high pressure regulator 25 is connected to the fuel return path 28c 'of the delivery pipe 25, the air venting operation is easily performed as in the first embodiment. be able to. Further, the delivery pipe 28 and the fuel supply rail 29 are the same as those in the first embodiment, and the piping length is not increased and the piping structure is not complicated.
[0112]
Further, the fuel from the high pressure fuel pump main body 33 circulates through the fuel return paths 29a 'and 28c' from the fuel forward paths 28c and 29a, so that the temperature of the fuel in the fuel supply rail 29 rises abnormally and bubbles are generated. Such a problem can be avoided.
[0113]
FIG. 25 is a view for explaining a third embodiment of the high-pressure fuel pipe, in which the same reference numerals as those in FIG. 1 denote the same or corresponding parts. In the second embodiment, the lower ends of the fuel supply rails 29, 29 are connected by a delivery pipe (communication pipe) 28 'extending in a direction perpendicular to the crankshaft 9, and the high-pressure pump body 33 is connected to the one fuel supply rail. The high pressure regulator 25 is connected to the upper part of the other fuel supply rail 29 '.
[0114]
According to the third embodiment, the lower ends of the fuel supply rails 29 and 29 are connected to each other by a delivery pipe 28 ′, and the high-pressure pump body 33 is placed on the upper portion of the one fuel supply rail 29. Since it is connected to the upper portion of the other fuel supply rail 29 ', the air in each of the fuel supply rails 29, 29' is naturally accumulated at the upper portion by the supplied fuel in the air venting operation, and one fuel supply rail. The air in 29 can be discharged from the high-pressure fuel pump 33 side, and the air in the other fuel supply rail 29 ′ is pushed out to the fuel return passage by opening the pressure regulating valve 25. 29 ', no air remains, and the air venting operation can be performed easily and reliably, and the high-pressure fuel pump main body 33 and the like can be It can be simplified piping structure with can be further shortened pipe length because it is connected to 29 and the like.
[0115]
  FIG. 26 is a view for explaining a fourth embodiment of the high-pressure fuel pipe, in which the same reference numerals as those in FIG. 1 denote the same or corresponding parts. In the fourth embodiment, the lower and upper portions of the fuel supply rails 29 and 29 are connected to each other by a delivery pipe (lower communication pipe) 28 ′ and a return pipe (upper communication pipe) 56 that extend in a direction perpendicular to the crankshaft. The return pipe 5 in which the high-pressure pump body 33 and the high-pressure regulator 25 are arranged at the upper part.With 6The high pressure pump main body 33 is connected to the delivery pipe 28 'disposed on the lower side by an introduction pipe 57 disposed in the vertical direction in the V bank, and the high pressure regulator 25 is disposed on the upper side. The return pipe 56 is connected.
[0116]
According to the fourth embodiment, the high-pressure pump main body 33 is connected to the lower delivery pipe 28 ′ by the introduction pipe 57 arranged vertically in the V bank, and the high-pressure regulator 25 is connected to the upper return pipe 56. Since the air naturally accumulates in the upper part as the fuel is supplied in the air venting operation, the air venting operation can be easily performed as in the above embodiments.
[0117]
Here, as shown in FIG. 27, the unit bracket 50 'is extended below the V bank, and the vapor separator 21 is fixed to the extended portion to unitize the high pressure fuel assembly. 21 can be attached to the engine so as to be located in the V bank. In this case, the length of the high pressure fuel pipe can be minimized, and the unit including the preload fuel system parts can be minimized. And the engine as a whole can be made more compact.
[Brief description of the drawings]
FIG. 1 is a block diagram showing the overall configuration of a fuel supply device for a fuel injection engine according to an embodiment of the present invention.
FIG. 2 is a plan view of the engine according to the embodiment.
FIG. 3 is a sectional plan view of the engine according to the embodiment.
FIG. 4 is a side view of the engine according to the embodiment.
FIG. 5 is a rear view of the engine according to the embodiment.
FIG. 6 is a cross-sectional side view of a cylinder bore portion of the engine according to the embodiment.
FIG. 7 is a cross-sectional plan view of the cylinder bore portion.
FIG. 8 is a plan view of a high-pressure fuel system assembly of the above-described embodiment device.
FIG. 9 is a rear view of the high-pressure fuel system assembly of the above-described embodiment device (viewed along arrow IX in FIG. 8).
FIG. 10 is a plan view of a high-pressure pump unit of the embodiment device.
FIG. 11 is a partial cross-sectional side view of the high-pressure pump unit of the embodiment device.
FIG. 12 is a plan view of a delivery pipe of the device according to the embodiment.
FIG. 13 is a sectional front view of a delivery pipe of the apparatus according to the embodiment.
14 is a cross-sectional side view (cross-sectional view taken along line XIV-XIV in FIG. 12) of the delivery pipe of the above-described embodiment device.
FIG. 15 is a plan view of a fuel supply rail of the device according to the embodiment.
FIG. 16 is a cross-sectional front view of a fuel supply rail of the above-described embodiment device.
FIG. 17 is a cross-sectional side view (cross-sectional view taken along line XVII-XVII in FIG. 16) of the fuel supply rail of the above-described embodiment device.
FIG. 18 is a cross-sectional front view of a delivery pipe and a fuel supply rail connecting portion of the above-described embodiment device.
FIG. 19 is a plan view of a unit bracket of the device according to the embodiment.
20 is a rear view of the unit bracket (as viewed in the direction of arrow XX in FIG. 19).
FIG. 21 is a side view of the unit bracket.
FIG. 22 is a plan view of a cylinder head of the engine.
FIG. 23 shows the fuel supply rail attached state of the engine.RefusalIt is a surface side view (XXIII-XXIII sectional view taken on the line of FIG. 22).
FIG. 24 is a schematic view showing a second embodiment of the high-pressure fuel pipe of the embodiment device.
FIG. 25 is a schematic diagram showing a third embodiment of the high-pressure fuel pipe of the embodiment device.
FIG. 26 is a schematic view showing a fourth embodiment of the high-pressure piping of the above-described embodiment device.
FIG. 27 is a rear view showing a modified example of the high-pressure fuel system assembly of the above-described embodiment device.
[Explanation of symbols]
2-fuel injection type 2-cycle engine
14 High pressure fuel system
15 preload fuel system
17 fuel tank
21 vapor separator
24a one way valve
24b high pressure pump bypass passage
25 High pressure regulator (pressure regulating valve)
25a pressure regulating valve bypass passage
30 pressure sensor (pressure inspection means)
31 Electromagnetic release valve (pressure release valve)
32 control device (residual pressure control means)
33 high pressure pump body

Claims (11)

A fuel injection valve that injects fuel into the cylinder bore, a high-pressure fuel pump that is driven by the engine and boosts the fuel to a required injection pressure, and a high-pressure fuel passage that supplies fuel from the high-pressure fuel pump to the fuel injection valve And a fuel injection device for a V-type vertical engine for an outboard motor comprising a high-pressure fuel system assembly formed by unitizing a fuel pressure adjustment valve for adjusting the fuel pressure in the high-pressure fuel passage to the injection pressure, The high-pressure fuel passage is made of aluminum alloy and is arranged in the horizontal direction, and the left and right fuel supply rails are made of aluminum alloy and are placed vertically in parallel with the crankshaft and connected to the fuel injection valve. The delivery pipe is connected to the left and right fuel supply rails above the uppermost fuel injection valve, and the delivery pipe and the high-pressure fuel pump. Are integrated via the bracket for unitization, the bracket is a fuel injection system of the V Katatate置 engine outboard motor, characterized in that it is fixed to the engine.   2. The fuel injection device for an outboard motor V-type vertical engine according to claim 1, wherein the high-pressure fuel pump incorporates the fuel pressure regulating valve.   In Claim 1 or 2, the high-pressure fuel pump, the fuel pressure adjustment valve and the delivery pipe are unitized in a first assembly, and the fuel supply rail and the fuel injection valve are unitized in a second assembly. A fuel injection device for a V-type vertical engine for an outboard motor, wherein the first and second assemblies are separately mounted on the engine.   3. An outboard motor V-type vertical installation according to claim 1, wherein both the high pressure fuel pump side portion and the fuel injection valve side portion of the high pressure fuel system assembly are fixed to the engine. Engine fuel injection device.   5. The fuel injection valve according to claim 1, wherein the fuel injection valve is fixed to the fuel supply rail by detachably fixing an adapter locked to the fuel injection valve to the fuel supply rail. Fuel injection device for V-type vertical engine for outboard motor.   6. The fuel injection valve according to claim 5, wherein when the fuel supply rail is pressed and fixed to the cylinder head, the adapter presses the fuel injection valve with a sealing member made of an elastic member on a seal surface on the cylinder head side. A fuel injection device for a V-type vertical engine for an outboard motor, which is fixed to a cylinder head.   7. The method according to claim 1, wherein at least a part of the high-pressure fuel system assembly is located in the V bank and fixed to the bottom of the V bank when viewed in the bisector direction of the V bank. A fuel injection device for a V-type vertical engine for an outboard motor.   8. The bank fuel supply rails according to claim 7, wherein the fuel supply rails for each bank are arranged in parallel to the crankshaft and closer to the inside of the V bank than the cylinder shaft, and the fuel injection valves connected to both the fuel supply rails are divided into two equal parts of the V bank An engine fuel injection device, wherein the fuel injection device is arranged substantially parallel to the line.   9. The vapor separator for storing fuel from a fuel tank and containing return oil from the high-pressure fuel system is unitized in the high-pressure fuel assembly according to claim 7, wherein the vapor separator is the V bank. A fuel injection device for an engine, wherein the fuel injection device is attached to the engine so as to be located inside.   A ship equipped with a high-pressure fuel pump that boosts fuel to a required injection pressure and a high-pressure fuel pipe that supplies fuel from the high-pressure fuel pump to a fuel injection valve, and injects fuel into an intake system or a cylinder bore. In the fuel injection device for a V-type vertical engine for an external unit, the high-pressure fuel pipe is made of an aluminum alloy, and two fuel supply rails arranged vertically in the cylinder head portion of each bank in parallel with the crankshaft. A delivery pipe which is made of an aluminum alloy and is arranged in a horizontal direction and connects the upper ends of the two fuel supply rails, and the delivery pipe and the high pressure fuel pump are integrated via a unitization bracket. The bracket is fixed to the engine, and is formed in the delivery pipe so as to be coaxial with the rail side connection hole formed in the fuel supply rail and the rail side connection hole. The joint pipe is inserted into the delivery pipe side connection hole, and a seal ring made of an elastic member having heat insulation is interposed between the joint pipe and the rail side connection hole and the delivery pipe side connection hole. A fuel injection device for a V-type vertical engine for an outboard motor. The back-up ring for preventing the seal ring from being deformed abnormally by pressure is interposed between the joint pipe and the rail-side connection hole and the delivery pipe-side connection hole. Fuel injection device for V-type vertical engine for outboard motor.

Images